The rising incidence of HIV/AIDS in the adolescent and young adult population in the United States is alarming. It is now estimated that 25% - 50 % of new cases in the U.S. are occurring in youth. Memphis and the surrounding area are no exception and its Southern location and large minority population has also impacted the rapid increase in cases. The successful conduct of clinical trials in adolescents requires a site with comprehensive medical services, compassionate and interested staff, case management services, a friendly clinic environment, and support for incidentals. St. Jude Children's Research Hospital (SJCRH) is a large research center that has provided comprehensive care for HIV-infected infants, children, adolescents, and pregnant women since 1988 with demonstrated excellence in clinical trials performance in the adolescent population. We propose an alternate practice site at the University of Tennessee (UT)/Methodist LeBonheur Health Systems (MLHS). MLHS is the site for UT's General Adolescent Clinics and MAYAH, the community Ryan White, Title IV, Youth Services Program. This alternate site will be staffed by St. Jude ATN personnel and compliment the main research unit in the identification, recruitment, and conduct of trials in HIV-at risk but uninfected adolescents. This model engages many community education, outreach, and testing facilities that will be key in implementing community mapping and vaccine preparedness studies. The specific aims of this project are: 1) To establish an effective adolescent clinical trials unit to further the scientific agenda of the Adolescent Trials Network through the recruitment and retention of HIV-infected and at-risk HIV-uninfected pre-adolescents, adolescents, and young adults into biomedical and behavioral clinical trials;2) To further develop existing community linkages to effectively establish a community-based primary prevention infrastructure that will support clinical trials of HIV prevention efforts, including vaccines, and other biomedical modalities;and 3) To contribute to the scientific agenda of the Adolescent Trials Network through the participation of investigators and site personnel in the development of protocol concept sheets and protocols. An ATU in Memphis would offer the combined advantages of an established, productive clinical research center with the proximity of a large at-risk population to maximize realization of the research efforts in the adolescent population.